#Gözlem islemleri : filter()

library(nycflights13)
## Warning: package 'nycflights13' was built under R version 4.4.1
library(magrittr) # needs to be run every time you start R and want to use %>%
## Warning: package 'magrittr' was built under R version 4.4.1
library(dplyr)   
## Warning: package 'dplyr' was built under R version 4.4.1
## 
## Attaching package: 'dplyr'
## The following objects are masked from 'package:stats':
## 
##     filter, lag
## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union
df <- flights
df
filter(df,day == 1)
filter(df,dep_time > 517)
filter(df,day == 2,dep_time > 520)
a <- filter(df,dep_delay > mean(dep_delay,na.rm = TRUE))
b <- select(a,carrier,dep_delay)

arrange(b,desc(dep_delay))
sample_n(df,10)  #Selects randomly observation
head(df,10) #Select First 10
top_n(df,10)  #Selects First 10 
## Selecting by time_hour
slice(df,100:110)  #Selects between 100-110